Refrigerating apparatus



H. C. HARVEY REFRIGERATING APPARATUS Filed Oct. 6, 1934 Z O ,/J wwmmws.7l/lao u RWQ Imi x E Nov. 2, 1937.

, y Il Patented Nov. 2, 1937 UNITED STATES PATENT" OFFICE '7 Claims.

The principal objects of the present invention are: first, to improveand make more certain and reliable the control of the introduction ofthehigh pressure refrigerant to the cooling coils, especially when thelatter are comparatively warm, as is the case in starting therefrigerating apparatus; to effect an economy in the utilization of thelow pressure refrigerant for cooling the high pressure refrigerant, andgenerally to make refrigerating apparatus more reliable and certain thanit is at present.

Other objects of the present invention will appear from the followingdescription at the end of which the invention will be claimed;

Generally stated the invention consists in the provision of a pressureresponsive device for regulating the control valve for the high pressurerefrigerant and acted upon by the occasional relatively high pressure ofthe low pressure refrigerant which occurs, for example, when theapparatus is started or is warm, in combination with a oat for normallyregulating the control valve for the high pressure refrigerant when theapparatus is in operation.

4'I'he invention also consists in the improvements to b'e presentlydescribed and4 finally claimed.

In the following'description, reference will be made to the accompanyingdrawing forming part hereof and in whic The single figure is atransverse sectional view of apparatus embodying features of the`invention.

In the drawing, I is the control valve that admits high pressure andcomparatively warm refrigerants to the cooling coils or the like, whichshould be kept full of refrigerants. The high pressure refrigerant fromthe compressor enters by pipe 2, coil 3 and sieve or screen 3ay and,after passing the control valvev I, passes at reduced pressure by way ofthe connection 4 to the cooling coils. 5 is a chamber subdivided intov aoat 'chamber 6 and an accumulator chamber 1, and low pressurerefrigerant from the coils enters it at 8. From the accumulator chamber1 there is a connection 9 back to the inlet of the compressor. I is apressure responsive device, shown as a ,bellows I I internally incommunication with the atmosphere as by the vent I2, and externally incommunication with the accumulator chamber 1 as by vents I3. I4 is afloat in the float chamber 6.

I1 is a lever pivoted intermediate of its ends. At

one end it is connected with the shank of the control valve 'I by apivotal nut I8 and a lock-nut I 9. The other end of the lever I1 isconnected With the head of the bellows II by a stud 20 through theintervention of a cushioning spring connection which affords lost motionat 2l. The last-mentioned end of the pivotal lever I1 is also slidablyconnected to the oat spindle 22 by the spring extension 23. 24 is alight cushioning spring for the spring extension 23, and the screw 24ais a means for adjusting the bellows Il. It is evident that, in thenormal expanded position of the bellows II, the float I4 can operatethe` valve I, and that when the oat I4 is seated in the oat chamber 6,the bellows by compression can operate valve I.

In starting, the oat I4 is seated and the valve I is opened. oI-Iighpressure refrigerant passes the valve I and with some reduction inpressure reaches the cooling coils which are warm,

`and rapid evaporation of the refrigerant develops abnormal pressure inthe chamber 5 before the cooling coils are full and before liquidreaches the float chamber from the coils, and this pressure acting uponthe bellows I l causes them to close the valve I, thus excluding highpressure refrigerant from the coils until the abnormally high rate ofevaporation in the coils and the consequent high pressure in the chamber5 are reduced. Thereafter liquid from the cooling coil enters thechamber 6 and the level of this liquid acting on the oat I4 causes it tocontrol the valve in the usual manner.

The above-described operations are repeated, as required, to keep thetemperature at the de- 'f sired point.

The described device and its connections replace a thermostatic deviceoften employed in refrigerating apparatus and responsive to thetemperature of the low pressure refrigerant, and the bellows `orpressure responsive device is less -liable to fail in operation, becauseits operation is not dependent upon a confined body of gas which, inpractice, is subject to leakage.

25 is a baille plate arranged opposite the low pressure refrigerantinlet 8 and it is perforated for the escape of liquid to the floatchamber 6. From the fioat chamber 6 liquid, especially oil or lubricant,flows over the dam 26 into the oil sump 21 from'which the lubricantenters the ciftake 9 to the compressor by way of the hole 29. Gas entersthe offtake 9 at the open upper end thereof. 28 is a baiiie platedepending into the oil sump 21.

Between the cold uid in the chamber 5 and in the sump 21 and the hotrefrigerant in the coil 3, heat exchange occurs, which effects economyin operation.

It will be obvious to those skilled in the art to which the inventionrelates that modifications may be made in details of construction andarrangement and in matters of mere form without departing from thespirit of the invention which is not limited to such matters orotherwise than the prior art and appended claims may require.

I claim:

1. In a refrigerating apparatus the combination of a control valve forhigh pressure refrigerant, a chamber subdivided into a float 'chamberand an accumulator chamber and into which low pressure refrigerant isadmitted, a float in said oat chamber, a bellows externally' exposed tothe pressure in said chamber and internally to the atmosphere, a pivotallever to one end of which the control valve is attached, a springconnection between the other end of the lever and the float, and a lostmotion spring connection between the last-mentioned end of the lever andthe bellows.

2. In a refrigerating apparatus of the type described, the combinationof, a chamber into which low pressure refrigerant is delivered and whichincludes an oil sump portion, a temperature exchange coil in contactwith the outside face of the wall of the sump, and connections forleading the high pressure refrigerant through said coil.

3. In a refrigerating apparatus of the type de. scribed the combinationof, a control valve for the high pressure refrigerant, a bellows forclosing said control valve and responsive to the occasional relativehigh pressure of the low pressure refrigerant, a uid level responsivedevice responsive to the level of the low pressure refrig- 4 erant fornormally regulating and opening and closing said control valve duringnormal operation of the apparatus, and mechanical connections betweensaid control valve and said bellows and said fluid level responsivedevice whereby either said bellows or said device may operate saidcontrol valve.

4. In a refrigerating apparatus, the combination of, a casing having achamber therein into which low pressure refrigerant is delivered, saidchamber including an oil sump, a temperature exchange coil in heattransfer relation to said oil sump, and connections for leading highpressure refrigerant through said coil.

5. In a refrigerating apparatus, the combination of, a control valve forhigh pressure refrigerant, a chamber sub-divided into a oat chamber andan accumulator chamber and into which low pressure refrigerant isadmitted, a float in said float chamber, a bellows exposed on theoutside to the pressure in said chamber and on the inside to theatmosphere, and mechanism interposed between the valve and the float andthe bellows whereby the valve is closed by the bellows when the pressureof the low pressure refrigerant is relatively high and opened and closedl and controlled by the float when the pressure of the low pressurerefrigerant drops.

6. In a refrigerating apparatus of the type described the combinationof, a control valve for the high pressure refrigerant, a float devicerespons'ive to the level of the low pressure refrigerant for opening andclosing and regulating the control valve when the pressure of the lowpressure refrigerant is comparatively low and the apparatus is inoperation, a pressure-responsive device internally vented to atmosphericpressure an'd externally exposed to the pressure of the low pressurerefrigerant and when the pressure of the low pressure refrigerant isrelatively high adapted to close the control valve, and mechanicalconnections between said valve, the float device and pressure device.

7. In a refrigerating apparatus, tion of, a casing divided into a floatchamber and an accumulator chamber, an oitake for low pressurerefrigerant having its inlet adjacent the top of the accumulatorchamber, a control valve for high pressure refrigerant, apressure-responsive device internally vented to the atmosphere andexternally exposed to the pressure in the float and accumulator chambersso as to operate in response to relatively high pressure of the lowpressure refrigerant to close said valve, a float mounted in the floatchamber and responsive to the liquid level of the low pressurerefrigerant to open and close and regulate said valve when the pressureof the low pressure refrigerant is relatively low, and lost motionconnections between said valve and said float and saidpressureresponsive device whereby the float controls said valve and thedevice occasionally closes it.

HERBERT C. HARVEY.

